A new formation (a subsequent coming together of the elements of a former grouping)(noun)
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Use "re-formation" in a sentence
"NFL, leading to settlement, re-formation of the NFLPA as a union, and a new CBA embodying the settlement."
"I am thinking that ... the re-formation of the faithful must happen primarily through input from abroad."
"It's no reflection on the quality of their back catalogue to suggest there's something a little surprising about the general rejoicing that seems to have greeted the news of Pulp's re-formation."